Interpretive Summary: Under certain culture conditions, organic fertilizers may be beneficial. However, considering channel catfish fry culture, benefits of organic fertilizers that are seen under different species and culture conditions would not be realized. Organic fertilizers are more labor-intensive to apply and cause an additional oxygen demand in the pond. Because channel catfish fry are offered high-protein feeds at stocking, the feed acts as a fertilizer probably negating any additional benefits from organic fertilizers. Desirable zooplankton for channel catfish fry culture can be increased through the use of inorganic fertilizers without the risks or labor associated with organic fertilizer. Any benefits seen from liberating free carbon dioxide from organic fertilizers under some culture conditions would be diminished in catfish nursery ponds because of the high alkalinity present in catfish culture waters.

Technical Abstract:
This paper reviews the assumed advantages and disadvantages of organic fertilizers and presents the case that the risks outweigh the benefits for channel catfish, Ictalurus punctatus, nursery pond fertilization. Under certain conditions, organic fertilizers may be beneficial to provide forage for zooplankton and release carbon dioxide. However, because of the culture methods used, the size of the ponds, the specific goals of catfish fry pond fertilization, the geographic location, the source water chemistry, the sediments, and the natural food preferences of channel catfish fry, benefits of organic fertilizers that are seen under different species and culture conditions would not be realized in channel catfish culture in the Yazoo-Mississippi floodplain. Organic fertilizers are more labor-intensive to apply and cause an additional oxygen demand in the pond. Because channel catfish fry are offered high-protein feeds at stocking, the feed acts as a fertilizer probably negating any additional benefits from organic fertilizers. Desirable zooplankton for channel catfish fry culture can be increased through the use of inorganic fertilizers without the risks or labor associated with organic fertilizer. Any benefits seen from liberating free carbon dioxide from organic fertilizers under some culture conditions would be diminished in catfish nursery ponds because of the high alkalinity present in catfish culture waters.